• 제목/요약/키워드: positive transfer

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Copper Interconnection and Flip Chip Packaging Laboratory Activity for Microelectronics Manufacturing Engineers

  • Moon, Dae-Ho;Ha, Tae-Min;Kim, Boom-Soo;Han, Seung-Soo;Hong, Sang-Jeen
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.431-432
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    • 2012
  • In the era of 20 nm scaled semiconductor volume manufacturing, Microelectronics Manufacturing Engineering Education is presented in this paper. The purpose of microelectronic engineering education is to educate engineers to work in the semiconductor industry; it is therefore should be considered even before than technology development. Three Microelectronics Manufacturing Engineering related courses are introduced, and how undergraduate students acquired hands-on experience on Microelectronics fabrication and manufacturing. Conventionally employed wire bonding was recognized as not only an additional parasitic source in high-frequency mobile applications due to the increased inductance caused from the wiring loop, but also a huddle for minimizing IC packaging footprint. To alleviate the concerns, chip bumping technologies such as flip chip bumping and pillar bumping have been suggested as promising chip assembly methods to provide high-density interconnects and lower signal propagation delay [1,2]. Aluminum as metal interconnecting material over the decades in integrated circuits (ICs) manufacturing has been rapidly replaced with copper in majority IC products. A single copper metal layer with various test patterns of lines and vias and $400{\mu}m$ by $400{\mu}m$ interconnected pads are formed. Mask M1 allows metal interconnection patterns on 4" wafers with AZ1512 positive tone photoresist, and Cu/TiN/Ti layers are wet etched in two steps. We employed WPR, a thick patternable negative photoresist, manufactured by JSR Corp., which is specifically developed as dielectric material for multi- chip packaging (MCP) and package-on-package (PoP). Spin-coating at 1,000 rpm, i-line UV exposure, and 1 hour curing at $110^{\circ}C$ allows about $25{\mu}m$ thick passivation layer before performing wafer level soldering. Conventional Si3N4 passivation between Cu and WPR layer using plasma CVD can be an optional. To practice the board level flip chip assembly, individual students draw their own fan-outs of 40 rectangle pads using Eagle CAD, a free PCB artwork EDA. Individuals then transfer the test circuitry on a blank CCFL board followed by Cu etching and solder mask processes. Negative dry film resist (DFR), Accimage$^{(R)}$, manufactured by Kolon Industries, Inc., was used for solder resist for ball grid array (BGA). We demonstrated how Microelectronics Manufacturing Engineering education has been performed by presenting brief intermediate by-product from undergraduate and graduate students. Microelectronics Manufacturing Engineering, once again, is to educating engineers to actively work in the area of semiconductor manufacturing. Through one semester senior level hands-on laboratory course, participating students will have clearer understanding on microelectronics manufacturing and realized the importance of manufacturing yield in practice.

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The Structural Stability and Electrochemical Properties of Fe Doped Li[Ni0.575Co0.1Mn0.325]O2 (Fe을 도핑한 Li[Ni0.575Co0.1Mn0.325]O2의 구조적인 안정성 및 전기화학적 특성)

  • Yang, Su-Bin;Yoo, Gi-Won;Jang, Byeong-Chan;Son, Jong-Tae
    • Journal of the Korean Electrochemical Society
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    • v.17 no.3
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    • pp.149-155
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    • 2014
  • In this study, a positive-electrode material in a lithium secondary battery $Li[Ni_{0.575}Co_{0.1}Mn_{0.325}]O_2$ was synthesized as precursor by co-precipitation. Cathode material was synthesized by adding iron. The synthesized cathode material was analyzed by scanning electron microscope and x-ray diffraction. The analysis of x-ray diffraction showed that the a-axis and c-axis is increased by doping iron. And $I_{(003)}/I_{(104)}$ is increased and $I_{(006)}+I_{(102)}/I_{(101)}$ is decreased. Through this result, it was confirmed that the structural stability is improved. And impedance measurements show that the charge transfer resistance ($R_{ct}$) is lowered by doping iron. Consequently, electrochemical properties are improved by doping iron. In particular, the cycle characteristics are improved at a high temperature condition (328 K). Structural stabilities are contributing to the cycle properties.

The mobility of the triangular hub cities against a cause of workers' transfer(Germany, Poland, Hungary) (노동자 이동의 원인에 대한 삼각 허브 도시의 유동성(독일, 폴란드, 헝가리))

  • Seo, Dae-Sung
    • Journal of Digital Convergence
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    • v.18 no.8
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    • pp.21-27
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    • 2020
  • This paper studies the impact of domestic and foreign economic activity on mobility among regions. The shortage of human resources and demand continues in Eastern Europeans. Especially Ukrainians, have entered the Polish labor market to make up for the scarce areas. As a result, Poland's supply and demand in Ukraine is disproportionate. Minimum wage increases are putting continued pressure on employers. Therefore, the regression equation in the form of job-seeker's economic activity ratio, y= AX2+B,(x=settlers) can be used to grasp the relationship between curves. According to the domestic and foreign workers who migrated, economic activities was rather than increasing the local population, the settlers of nearby large cities is more proportional. Empirical analysis has shown that the human resource hub has increased migration to large cities and industrial. The hub 'A'nation has been created for mobility in 4th wave re-industry, and the same re-industrialization (N2) in other cities has attracted nearby human resources, but not settle. After all, the hub relationship between N1 and N2 is a mobile relationship. Due to wage inequality or a positive wellbeing chasm, workers are not settled plant area but a nearby city, or commuting between borders is easy to go into the hub central city. However, this proved on emerging from the relatively temporary settlers in the AI era.

A Study on the Problem of Insurance Terms Choice in the Marine Cargo Insurance Contract (해상적하보험계약(海上積荷保驗契約)에 있어서 보험조건선택(保險條件選擇)의 문제점(問題點)에 관한 고찰(考察))

  • Ra, Gong-Wu;Han, Sang-Hyun
    • Korean Business Review
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    • v.11
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    • pp.415-437
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    • 1998
  • On choosing insurance terms it would be a reasonable choice to choose insurance terms in proportion to how much risk is to be with considering of how much risk is exactly to be in a cargo's owner of his or hers as there are conditions such as a character of cargo, a packing condition, a loading ship, a shipping section, and a premium. But when we see on the present state of the statistical insurance table, the effects are entirely different from it stated above and these serious problems are of both the problem to prove who is on duty and the problem to cover how much the indemnity are to be. When we see a shipper as the insured, in the last 3 years that all risks has been more than 95 percent is to prove the reason mentioned above and there would be an intention for the shipper to transfer a claim for the indemnity to the insurer to evade from the complexity. Also when we see how much both I.C.C and New I.C.C is used, New I.C.C has been used less two times than I.C.C, that is due to the restriction of the scale of covering the indemnity. So both the introduction of trade clause as to insured in the same line of business and the positive application, taking into account of the principle of proving who is on duty and the scale of covering the indemnity, are to be accomplished.

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Transnational Migration and Socio-Spatial Changes in S. Korea (초국적 이주와 한국의 사회공간적 변화)

  • Choi, Byung-Doo
    • Journal of the Korean Geographical Society
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    • v.47 no.1
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    • pp.13-36
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    • 2012
  • This paper is to reconsider comprehensively and systematically major issues on transnational immigrants, increased rapidly since the beginning of the 1990s, and their impacts on socio-spatial changes in S. Korea. Foreign immigrants who have moved on the contexts of unevenness of globalization and advancces in transport & telecommunication technology on the global level and of economic development and shortage of cheap and unskilled workers have been distributed unevenly, concentrating on the Capital region and local areas with industrial complexes. Foreign workers seems to have some negative influences on regional economies in the long-term, though positive in the short-term. Domestic people seem to have an ambivalent attitude which accepts necessity of multi-culture, while simultaneously continues to be self-confident on ethnic homogeneity. The Korean government has launched multicultural policies for foreign immigrants by the mid-2000, but still continues some policies with assimilationism and differential exclusionism, marginalizing them socio-spatially, while lacking local government's policy and programmes. In conclusion, in order to resolve these problems and to transfer multicultural societal space of Korea, a geography of transnational migration which promotes especially discourse and policy with authentic multiculturalism, extending roles of local government, and ensuring glocal citizenships.

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Exploring the Spatiality of School Choice through Residential Mobility: A Preliminary Case Study of Elementary School Students in Seoul (거주지 이동을 통한 학교 선택의 공간성에 관한 연구: 서울시 초등학생의 전학 양상을 사례로 한 시론적 분석)

  • Lee, Hwajung;Lee, Sang-Il;Cho, Daeheon
    • Journal of the Korean Geographical Society
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    • v.48 no.6
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    • pp.897-913
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    • 2013
  • The main purpose of the paper is to examine the spatial characteristics of school choice through residential mobility by conducting a correlation analysis on the relationships between the middle schools' entrance rates to special high schools and the elementary schools' net transfer rates. Analyses are done at both the individual school level and the school catchment area level. Prior to the calculation, the two variables involved in the correlation analysis are transformed via a standardization equation, and the standardized scores are mapped and explored. Both the global and local correlation analyses are done for the standardized variables. Main findings are twofold. First, the global correlation analysis reports that there exists a statistically significant correlation between the two variables at both the analytical levels. Second, albeit the prominent positive correlation at the global level, the local analysis reveals the existence of a considerable level of spatial heterogeneity in terms of bivariate association. While several school catchment areas with very high local correlation coefficients (the HH association type) are popped up, other areas with various types of bivariate association including ones even opposite to the global trend are also observed.

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Analysis of Economic Effects and Basic Theoretical Frameworks of ITQ Fishery Management - Focusing on the Red Crab Trap Fishery - (ITQ 어업관리의 기본이론과 경제적 효과분석 - 붉은대게어업을 중심으로 -)

  • Lee Sang-Go;Lee Yong-Soo
    • The Journal of Fisheries Business Administration
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    • v.36 no.3 s.69
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    • pp.119-139
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    • 2005
  • The purpose of this paper is to provide information that will help both fishing industry and fisheries authority understand the principals of individual transferable quota(ITQ) fishery management. Theoretical frameworks and primary features of ITQ fishery managemenet are the assignment of exclusive property rights for harvest of common - property fisheries resources. An ITQ fishery management is fundamentally different from the conventional fishery management and it gives an individual fisherman the right to catch a specified quantity of fish, his quota. With ITQ, fisherman's quotas are transferable, in whole or in part. An ITQ is a property with certain rights of use, namely, the right to catch a given quantity and species of fish in a specific location during a specific period of time. The right is exclusive in the sense that no one else has the right to use the quota without the owner's permission. The property may be assigned, traded, and exchanged; i.e., the owner has the right to transfer an ownership to others. An ITQ fishery management leads to both economic efficiency and resource conservation. Motivations to overexploit stocks and to overcapitalize should be lessened because fishermen no longer have to compete for limited resources. There are significant positive net benefits and advantages with ITQ fishery management than without. The potential benefits and advantages of ITQ fishery management include increased profits, economic stability, improved product quality, safer working conditions, less gear conflict, elimination of the race - to - fish phenomenon, less by - catch, less gear loss, improved investment climate, mitigation of market gluts, waste reduction, addition to fisherman's wealth, and compensation for fisherman exiting the fishery. As an independent observe to Red Crab Trap Fishery some of the benefits, problems, and effects, an ITQ fishery management in Red Crab Trap Fishery is still far from to be implemented. Many different and difficult aspects (biological, socioeconomics, administrative) are involved considering the implementation of ITQ fishery management in Red Crab Trap Fishery. Among other fishery management tools, the implementation of ITQ fishery management in Red Crab Trap Fishery is considered to be the best in achieving the better conservation of fisheries resources and their more economic and rational exploitation. Korean fisheries authority should pay great attention to the experience of the economic effects of the ITQ fishery management in Red Crab Trap Fishery in the hope of being able to implement at least some of those experiences into the Korean fishery management.

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A Comparative Study on the Compliance Program(CP) of Strategic Export Control System between Korea and Japan (전략물자 수출통제 자율준수제도(CP)에 관한 한.일 비교 연구)

  • Shim, Sang-Ryul;Shao, Dan;Joo, E-Wha
    • International Commerce and Information Review
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    • v.13 no.4
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    • pp.297-321
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    • 2011
  • Under the UN Security Council Resolution 1540/1810 in 2004 to restrict the proliferation of WMD (weapons of mass destruction) and their means of delivery, many countries have taken great efforts to, control the export of strategic items, thereby preventing the transfer of ABCM (atomic, biological, chemical weapons, missiles) and technologies and goods related to conventional weapons or dual-use items, Compliance Program (CP) in Korea or Internal Compliance Program(ICP) in Japan refers to a company's internal system or rules to comply with the export control laws and regulations, and is to prevent the unintentional illegal export of strategic items. This paper analyzes the Compliance Program (CP) of strategic export control system between Korea and Japan. Both countries have very similar legal frameworks under the guiding principles of multilateral export control regimes. However, there are some differences in actual procedures, classification service, supporting system, export license, sanctions for illegal exporters, etc. Korea should take more active and customer-oriented measures to promote the Compliance Program (CP) into Korean export companies for better awareness and positive attitude, practical information and education, smoothy government-firm communication, closer cooperation between Korea and Japan, etc.

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A Study on Life Experience by Persons with Mental illness - Focusing on the Experience after the Onslaught of Mental Illness - (정신장애인의 생애경험에 관한 연구 - 정신질환발병 이후의 경험을 중심으로 -)

  • Park, Eun-Ju
    • Korean Journal of Social Welfare
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    • v.63 no.1
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    • pp.5-28
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    • 2011
  • This study, based on the research on the history of life, aimed to recompose and analyze into what life progressive structure the life experience by the mentally ill, after the onslaught of the disease, developed in a bid to understand the risk progress in the mentally ill's life, and to determine what contributed to the current stabilized recovery and adjustment. Five mentally ill persons participated in the study, and Sch$\ddot{u}$tze's narrative interview was used to gather data. The gathered data were analyzed according to Sch$\ddot{u}$tze's process structure of life. The interviewees' life experiences were chronologically organized as understood, and significant stories were recomposed that not only brought about changes but also helped overcome their disabilities in the process of treatment and rehabilitation after the onslaught of the disease. As a result, their experiences were recomposed into the stage of onslaught of the mental illness and confusion, and into the stage of intensive treatment and rehabilitation. The former was categorized into suppression by the disease, repetition and endurance of the painful life, and separation from their family and frustration. The latter was categorized into the rediscovery of self through social role change, others who helped realize the life potential, the expansion of mental health services in the community, obstacle to the integration of communities, re-integration of family relationships, re-analysis of experience of the disease through the examination of the life prior to onslaught of the disease, and expectation for the future. Also, these themes were comparatively examined so as to examine the crisis progress in the mentally ill's life after the onslaught of the disease, as well as the life transfer process through positive rehabilitation. Lastly, on the basis of these results, important areas of mental health services for the mentally ill were discussed.

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Study on In Vitro Maturation and Culture of Immature Oocytes Collected from Ovaries of Infertile Women (불임 여성의 난소로부터 회수된 미성숙 난자의 체외 성숙과 배양에 관한 연구)

  • Lee, Seok-Yoon;Son, Won-Young;Yoon, San-Hyun;Lee, Won-Don;Park, Chang-Sik;Lim, Jin-Ho
    • Clinical and Experimental Reproductive Medicine
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    • v.30 no.4
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    • pp.333-340
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    • 2003
  • Objective: This study was performed to examine the maturation and the development to the blastocyst stage of immature oocytes collected from patients with high risk of ovarian hyperstimulation syndrome (OHSS). Materials and Methods: Cumulus-oocyte complexes (COCs) were collected following only HCGpriming for non stimulated IVF-ET cycles of the patients. At the time of oocyte collection, COCs were classified into three groups in accordance with their appearance (Group I: oocytes with dispersed cumulus cells; Group II: oocytes with compacted cumulus cells; Group III: oocytes with sparse cumulus cells). The in vitro maturation and blastocyst development rates of the COCs were compared among these groups. From August 2001 to June 2002, 48 IVM/IVF-ET cycles from 42 patients (mean age: $32.4{\pm}3.8$ years) were performed. To prevent the occurrence of OHSS, the patients were primed with 10, 000 IU HCG alone 36 h before oocyte collection without gonadotropin stimulation. Oocytes were aspirated on cycle days from 7 to 13. The normal COCs were classified into three groups according to their appearance. The aspirated immature oocytes were cultured in YS maturation medium containing 30% (v/v) human follicular fluid (HFF), 1 IU/ml FSH, 10 IU/ml HCG and 10 ng/ml rhEGF. Fertilization was induced by intracytoplasmic sperm injection (ICSI). All zygotes were co-cultured with cumulus cells in $10{\mu}l$ YS medium containing 10% HFF until day 7 after oocyte collection. Blastocyst transfer was performed on day 5 after ICSI. Results: Th e mean number of oocytes cultured in the IVM/IVF cycles was $24.7{\pm}10.6$. Of 1185 COCs, those assigned to Group I, II and III were 470 (39.7%), 414 (35.0%) and 301 (25.4%), respectively. The maturation rate (94.5%, 444/470, p<0.05) in Group I was significantly higher than those of Group II (62.8%, 260/414) and Group III (73.1%, 220/301). Especially, 30.9% of COCs in Group I (145/470) was matured on the day of oocyte aspiration. There were no differences in the rates of fertilization and cleavage among the three groups. The development rate to the blastocyst stage in Group I (54.6%, 206/377, p<0.05) was also significantly higher than those in Group II (33.0%, 68/206) and Group III (30.1%, 52/173). Twenty-four clinical pregnancies (50.0%) was obtained and 22 pregnancies (45.8%) are ongoing. Implantation rate in the present study was 24.6%. Conclusion: These results suggest that there is a positive correlation between the appearance of COCs and the developmental competence of the immature oocytes in non stimulated IVM/IVF cycles.